Research Article |
Corresponding author: Liliia Budniak ( stoyko_li@tdmu.edu.ua ) Academic editor: Paraskev Nedialkov
© 2022 Liudmyla Slobodianiuk, Liliia Budniak, Halyna Feshchenko, Andriy Sverstiuk, Yuri Palaniza.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Slobodianiuk L, Budniak L, Feshchenko H, Sverstiuk A, Palaniza Y (2022) Quantitative analysis of fatty acids and monosaccharides composition in Chamerion angustifolium L. by GC/MS method. Pharmacia 69(1): 167-174. https://doi.org/10.3897/pharmacia.69.e76687
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Chamaenerion angustifolium L. widely known as fireweed, has significant natural resources in Ukraine. It has long been used in folk medicine as a sedative, analgesic, astringent, antimicrobial, anti-inflammatory, antisclerotic, wound healing, and diaphoretic agent. These properties are the result of the availability of many groups of biologically active compounds such as flavonoids, hydroxycinnamic acids, tannins, ascorbic acid, polyphenols, macro- and microelements. The aim of the study was to determine the content of fatty acids and monosaccharides of the herb. The qualitative composition and quantitative content of these biologically active compounds were determined using a GC/MS method. The results of the analysis showed that the herb of fireweed has monosaccharides, such as D-ribose, D-arabinose, D-mannose, D-glucose, D-galactose, and Myo-inositol. D-glucose presented in raw materials in the highest amount, it is content in the herb was 11.23 mg/kg. Among fatty acids, the mono-, polyunsaturated and saturated acids were determined. The content of polyunsaturated fatty acids of the total fatty acids was 53.19%, monounsaturated – 4.92%, and saturated – 41.89%. Linolenic, palmitic, and linoleic acids dominated among the determined twelve fatty acids, their content was 1.82 mg/kg, 1.74 mg/kg, and 1.10 mg/g.
Chamerion angustifolium L., fireweed, fatty acids, monosaccharides, GC/MS
Medicinal plants, especially those that mankind has long used in folk medicine, are a source of many biologically active substances (flavonoids, hydroxycinnamic acids, tannins, etc.). The complex of substances contained in plants determines the polyvalence of their action, affecting various systems and organs of the human body (
In recent decades, scientists have been interested in the phytochemical composition and pharmacological properties of plant materials belonging to the willowherb family (Onagraceae). Initially, this was due only to chemotaxonomy, as different species of this family contain large amounts of flavonoids, which are often considered important chemotaxonomic markers (
Among many promising medicinal plants, Chamaenerion angustifolium, widely known as fireweed (Onagraceae), which has significant natural resources in Ukraine. C. angustifolium has long been used in folk medicine as a sedative, antimicrobial, adstringent, and analgesic, wound healing, anti-inflammatory, diaphoretic, emollient and antisclerotic agent (
C. angustifolium, which grows in the Krasnodar territory, contains a large number of polysaccharides, cellulose and lignins. Also, the plant contains carotene (3.16 mg%), rutin (15.68 mg%) and anthocyanins (30.11%) (
The leaves of C. angustifolium contain organic acids, tannins, anthocyanins, carotenoids, flavonoids (quercetin, kaempferol, myricetin), ascorbic acid, pectins, polysaccharides, lignins, coumarins, tannins, sterols, triterpenes, carotenes, plain phenols and polyphenolic compounds (
Studies by Lithuanian scientists have also shown the presence of phenolic compounds in samples of freshly harvested and dry raw materials of C. angustifolium. Enotein B, rutin and quercetin predominated in all samples; caffeic and chlorogenic acids were also identified. Volatile compounds were studied and it was found that all investigated samples contain α- and β-caryophyllenes (
Previous studies revealed various groups of biologically active substances in C. angustifolium, but monosaccharides and fatty acids were not studied. Based on the literature data and analysis of the chemical composition of biologically active substances of Chamerion angustifolium, it is important to study the monosaccharides and fatty acids composition of this plant.
The aboveground part of C. angustifolium was collected during flowering period in the Ternopil region (Ukraine) in 2017 (
All applied reagents were of analytical grade (≥ 95% purity). Standard reagents, including D-mannose, L-rhamnose, D-ribose, D-galactose, D-xylose, D-arabinose, D-glucose, D-fructose, D-saccharose, D-fucose, and D-sorbitol, were purchased from Sigma-Aldrich Chemical Co. (USA), as well as nonadecanoic acid, methanol, hydroxylamine hydrochloride, pyridine, hydrochloric acid, dichloroethane, ethyl acetate, and heptane (
Fatty acids were identified by the reference standard mixture FAME (Supelco, Belle Fonte, PA, USA).
GC/MS analysis of monosaccharides composition of the herb was performed using gas chromatograph Agilent 6890N with 5973inert mass detector (Agilent Technologies, USA) and a capillary column HP-5MS (30 m × 0.25 mm × 0.25 µm). The oven temperature was initially set at 160 °C, held for 8 min, then raised to 240 °C at the rate of 5 °C/min and finally kept at this point for 6 min. Injections were made in the split mode 1:50 (
Sample Preparation. For the extraction of free monosaccharides, 10 mL of methanol and internal standard (sorbitol) (0.5 mg per sample) was added to 500 mg of powdered raw material. The extraction took place at 80 °C for 4 h. In this regard, 2 mL of the extract was evaporated to dryness and 0.3 mL of derivatization reagent (32 mg/mL of hydroxylamine hydrochloride in pyridine/methanol (4:1 v/v)) was added. The extract was kept at 75 °C for 25 min. Then, for acetylation of aldonitrile derivatives, 1 mL of acetic anhydride was subsequently added to the samples and incubated at 75 °C for 15 min. Two mL of dichloroethane was added and the excess of the derivatization reagents was removed by double extraction with 1 M hydrochloric acid and water. The dichloroethane layer was dried and dissolved in 300 μL of the mixture of heptane/ethyl acetate (1:1 v/v) (
Identification of monosaccharides was based on their retention times compared to standards and mass library NIST 02. Quantification was done by using the internal standard of sorbitol added to the sample.
GC/MS analysis of fatty acids was performed using gas chromatograph Agilent 6890N with mass detector 5973 inert (
Accurate mass (0.5 g) of the raw material was refluxed with a 3.3 mL mixture containing (methanol: toluene: sulfuric acid (44:20:2 v/v)) and 1.7 mL of internal standard solution (undecanoic acid in heptane). The sample was maintained in the ultrasonic water bath at 80 °C for 2 h. The resulting mixture was allowed to cool and centrifuged for 10 min at 5000 × g. Then 0.5 mL of the upper heptane phase containing methyl esters of fatty acids were separated (
The compositions of the product obtained were identified by comparison of their mass-spectrums with data obtained from the NIST 2008 database. The quantitative content of fatty acids was done using the internal standard of undecanoic acid in heptane solution added to the sample.
The analytical method was validated in terms of linearity, detection limit, precision, stability, repeatability, and recovery. A total of 10 standard monosaccharides (D-mannose, L-rhamnose, D-ribose, D-galactose, D-arabinose, D-fructose, D-xylose, D-glucose, D-saccharose, D-fucose) were used for these tests.
All calibration curves were established by plotting the chromatographic peak area of monosaccharide derivatives versus the concentration of the corresponding monosaccharide solution shown in Table
Calibration curves, linear ranges, limits of detection (LOD), and limit of quantification (LOQ) for individual monosaccharides after GC/MS analysis.
Monosaccharide | Regression equations | Correlation coefficient R2 | Limit of detection LOD, µmol/L | Limit of quantification LOQ, µmol/L |
---|---|---|---|---|
ribose | y = 0.0308x + 0.6322 | 0.9998 | 0.19 | 0.63 |
rhamnose | y = 0.0728x + 0.7383 | 0.9999 | 0.83 | 2.76 |
arabinose | y = 0.0211x + 0.1918 | 0.9999 | 0.22 | 0.73 |
fucose | y = 0.0535x + 0.1376 | 0.9998 | 0.54 | 1.80 |
xylose | y = 0.0254x + 0.4005 | 0.9995 | 1.15 | 3.83 |
mannose | y = 0.0318x + 0.1231 | 0.9999 | 0.37 | 1.23 |
glucose | y = 0.0235x + 0.1588 | 0.9999 | 0.29 | 0.97 |
galactose | y = 0.0271x + 0.7549 | 0.9998 | 0.74 | 2.47 |
fructose | y = 0.0177x + 0.5006 | 0.9996 | 0.57 | 1.90 |
saccharose | y = 0.0163x + 0.5701 | 0.9991 | 0.78 | 2.60 |
The performance of the proposed method of determining fatty acids was tested using a number of qualitative and quantitative parameters. The identification criteria for working range determination (calibration curve range) were LOQ, linearity, and calibration model fits (correlation) (
Fatty acid | Regression equations |
Correlation coefficient R2 | Limit of detection LOD, µmol/mL | Limit of quantification LOQ, µmol/mL |
---|---|---|---|---|
undecanoic acid | y = 0.0015x + 0.0236 | 0.999 | 0.0086 | 0.0143 |
palmitic acid | y = 0.0013x + 0.0237 | 0.997 | 0.0435 | 0.0522 |
palmitoleic acid | y = 0.0069x + 0.0273 | 0.995 | 0.0176 | 0.0293 |
heptadecanoic acid | y = 0.0102x + 0.0292 | 0.995 | 0.0204 | 0.034 |
linoleic acid | y = 0.0164x + 0.0487 | 0.998 | 0.0128 | 0.0256 |
linolenic acid | y = 0.0106x + 0.0402 | 0.999 | 0.015 | 0.0432 |
stearic acid | y = 0.0117x + 0.0295 | 0.999 | 0.0265 | 0.0318 |
11-eicosenoic acid | y = 0.0475x + 0.0402 | 0.996 | 0.015 | 0.0249 |
arachidic acid | y = 0.0027x + 0.0125 | 0.997 | 0.0157 | 0.0262 |
behenic acid | y = 0.0032x + 0.0144 | 0.995 | 0.0206 | 0.0343 |
hexacosanoic acids | y = 0.0132x + 0.0552 | 0.996 | 0.0192 | 0.032 |
The monosaccharides extracted from C. angustifolium was determined based on GC/MS analysis of the alditol acetates, formed after acid hydrolysis. The number of monosaccharides components of the herb is represented in Table
No. | Retention time | Name | Content of the free monosaccharides, mg/kg |
---|---|---|---|
1. | 10.96 | D-ribose | 0.31±0.02 |
2. | 11.41 | D-arabinose | 0.35±0.01 |
3. | 17.08 | D-mannose | 0.5±0.02 |
4. | 17.36 | D-glucose | 11.23±0.06 |
5. | 17.85 | D-galactose | 1.36±0.03 |
6. | 20.07 | Myo-inositol | 1.37±0.03 |
The major monosaccharide detected was D-glucose (11.23 mg/g). Glucose is one of the three dietary monosaccharides, along with galactose and fructose, which are absorbed directly into the bloodstream during digestion (
The content of fatty acids is presented in Fig.
No. | Retention time | Common name of fatty acid (IUPAC) | Chemical nomenclature | Quantitative content of methyl esters of fatty acids | |
---|---|---|---|---|---|
mg/kg | % of the total | ||||
Saturated acids | |||||
1. | 39.57 | Palmitic (hexadecanoic) | С 16:0 | 1.74 | 31.69 |
2. | 41.90 | Margaric (heptadecanoic) | C17:0 | 0.03 | 0.55 |
3. | 44.15 | Stearic (octadecanoic) | С 18:0 | 0.23 | 4.19 |
4. | 48.38 | Arachidic (eicosanoic) | С 20:0 | 0.22 | 4.00 |
5. | 52.32 | Behenic (docosanoic) | С 22:0 | 0.05 | 0.91 |
6. | 62.74 | Cerotic (hexacosanoic) | С 26:0 | 0.03 | 0.55 |
Monounsaturated acids (ω-7 and ω-9) | |||||
7. | 39.46 | Palmitoleic (9-hexadecenoic, ω-7) | С 16:1 | 0.10 | 1.82 |
8. | 43.71 | Oleic (octadecenoic, ω-9) | С 18:1 | 0.13 | 2.37 |
9. | 48.20 | Gondoic (11-eicosenoic, ω-9) | C20:1 | 0.04 | 0.73 |
Polyunsaturated acids (ω-3 and ω-6) | |||||
10. | 43.47 | Linoleic (octadecadienic, ω-6) | С 18:2 | 1.10 | 20.04 |
11. | 43.63 | Linolenic (octadecatrienic, ω-3) | С 18:3 | 1.82 | 33.15 |
Amount of saturated fatty acids | 2.3 | 41.89 | |||
Amount of unsaturated fatty acids | 3.19 | 58.11 | |||
Total | 5.49 | 100 |
The content of mono- and polyunsaturated fatty acids in the herb was greater than saturated fatty acids. The unsaturated coefficient was 1.39.
C. angustifolium herb contained palmitic acid as the main saturated acid. Its content was 1.74 mg/kg (31.69% of the fatty acids total content). The amount of other saturated acids such as behenic, stearic, arachidic, margaric, and cerotic was much lower. Polyunsaturated fatty acids of the sample were represented by linolenic and linoleic acids, their content was 1.82 mg/kg, and 1.10 mg/kg. Linoleic and linolenic acids are essential for human nutrition and are called vitamin F (
Three monounsaturated acids: palmitoleic, oleic, and gondoic acids were also determined among the unsaturated fatty acids in the herb. Palmitoleic acid is one of the most common ω-7 fatty acids. This acid is a lipokine that has potential nutraceutical use to treat nonalcoholic fatty liver disease. Also, palmitoleic acid has anti-inflammatory and antidiabetic activities (
The fatty acids and monosaccharides present in the herb of fireweed have been studied by GC/MS analysis. The results of monosaccharides analysis showed that the herb of fireweed accumulated D-glucose (11.23 mg/kg), Myo-inositol (1.37 mg/kg), D-galactose (1.36 mg/kg), D-mannose (0.5 mg/kg), D-arabinose (0.35 mg/kg) and D-ribose (0.31 mg/kg). The content of polyunsaturated fatty acids of the total fatty acids was 53.19%, monounsaturated – 4.92%, and saturated – 41.89%. Linolenic, palmitic, and linoleic fatty acids were dominant, these content was 1.82 mg/kg (33.15%), 1.74 mg/kg (31.69%), and 1.10 mg/kg (20.04%).